cms tracker system test

Waclaw Karpinski General meeting 13.06.02

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CMS TRACKER SYSTEM TEST

Outer Barrel –TOB

Inner Barrel –TIB

End cap –TEC

•TIB•TOB•TEC

Different GeometriesOne Readout ArchitectureOne Powering Schema


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Power supplies

o Situated in counting room

o Implement a unipolar scheme o PS modules power groups of ~60APV

[email protected] =10A, [email protected] =4A I@0V =14A

o Each PS module equipped with 2 HV channels for detector bias

o Floating LV, HV power supplies of each power group, their Return Lines connected inside the detector to the Common Detector Ground

Power Cables 140 m longo Voltage drop = 5Vo Use of sens wires to compensate the voltage dropo Multipolar cable with low inductance , high capacitance to minimize

voltage overshoots due to current variations

Power Supplies and Cables


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Definition of the System Test

The tracker has to enter its production phaseNeed to validate a complete subset of it

o Validate designso Tune design detailso Verify/optimize integration of components

Focus is not on component characterization, but on

overall system performance

The subsets: (for TIB/TOB/TEC)

A number of final modules (sensors +frontend hybrid) integrated on the final mechanical support structure equipped with:

o interconnect boards o optical digital links and electronics for control o optical analogue links for readout o power supplies + 100m MSCable o cooling


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What is necessary to prove it works

Moduleso Noiseo Physics signals (ß-source, Laser), SNRo APV settingso Detector leakage currents

Compare with corresponding measurements taken with individual modules in the “single module setup” (i.e. electrical readout)

Analogue readout chaino Optical link gain and bias point o timing alignment of modulso Noise contributions, Crosstalk, Common mode effects o Operation margin

Control chaino Noise immunity ( Grounding, cabling, shielding)o Operation margino Redundancy

Long Term Stability and Temperature stability of the system


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Interconnect boards, mother boards

Signal Integrity

o the distribution of the fast control signals: clock, reset and back plane pulses,

Power distribution

o voltage drops; uniformity of supply voltage distribution

o Behaviour of full loaded system due to sudden variation in

current consumption in correlation with:

o large inductance of the long cables

o slow reaction time of PSU

Protection against over-voltage?



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Mechanics

o mechanical compatibility of the various components with the mechanical support structure

o mechanical stress of the modules due to their fixation on cooling system and interconnect boards

o Deformation upon cooldown due to different CTE´s

Ambient parameters

o temperatures of the modules

o temp. of various elements

o humidity in several spots



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Tracker Inner Barrel System Test

Phase 1 (April-July): Readout of 1 to 6 modules with a complete (analog & digital) optical link; test with prototype PSUs with long cables.

- Phase 2 (July-December): mechanical and electrical integration and tests of a small part of TIB:

- 6 double sided modules on Layer #1 cylinder - 12 single sided modules on Layer #3 cylinder


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LAB set-up in Florencecopper readout : UTRI+FEDoptical readout: Opto Hybrid + Fiber + Opto Receiver + Diff. Buffer +FED

PC withFED, FEC and TSC CCU

Detector andOpto Hybrid

Interface Board

(UTRI)



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T(ns)

Optical Readout57 ADC

60 ADC

Copper Readout

T(ns) AD counts

NC

h/b

in

AD

co

un

tsA

D c

ou

nts

AD counts

NC

h/b

in

Optical Readout

Noise 1.47 ADC

Noise1.18 ADC


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Signal to noise

Signal equivalent to roughly 2 MIPs

Copper readout: S/N =42

Optical readout: S/N =48



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The rod componentsThe rod components

InterConnect Bus

InterConnect Cards

Module frame

Cooling pipe

Patch panel

Module support blocks

15 cm

110 cm

Tracker Outer Barrel System Test


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Detailed electrical test of IC bus + IC cards, with 12FE- Hybrids and

8 OptoHybrids (almost full load)

o Check of the signal integrityo Optimization of the impedance matchingo Measurement of the voltage drop along the buso Test of I2C communication


ResultsResults

The design of IC Bus and IC Cards is correct – signals are very clean A few details have been fixed/optimized

Optical link commissioned on a single channel setup

Nominal gain of the link verified

Optimization of the bias point


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Next step:Integrate a rod with electrical components and real modules

Build an Alu box, gas tight, with patch panel for pipes (cooling and dry air) and other services (It can house 2 rods)

Add external temperature and humidity probes

Commission a cooling system with C6F14



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Current status:

All modules working properly and read out under bias

External temperatures probes also read out

Cooling running smoothly

Grounding scheme similar to the “final” one implemented

Now ready to start quantitative measurements

Study sensitivity to noise on the power lines / groundingGo to the tracker operating temperatureInstall 12 detectors in the second rod (DS rod)Add a second rod

Further steps



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•28 Si-detectors•28 FE hybrids•28 Optohybrids•2 CCUM•4 IC Boards

Tracker Endcap System Test

Front petal

front petal back petal3 power groups : 1. Ring #1, #2 48 APVs 24 APVs 2. Ring #3, #4, #6 44 APVs 32 APVs 3. Ring #5, #7 44 APVs 56 APVs

A-side B-side


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Design verification of petals

o mechanics, doneo electrical performance of the interconnect board, doneo deformation after cooldown tested

System test in 4 steps:

1. Test of the 2nd detector group (rings #3, #4, #6)

2. Test of the 3rd detector group (rings #5, #7)

Fully equipped but without Si-Sensors,

3. Test of the 1st detector group (rings #1, #2) Fully equipped but without Si-Sensors,

Results expected by the end of this year

4. Full System Test for Front and Back petal

o fully equipped with Sensors and front end electronics

o with final cables and power supplies

Final results expected in spring 2003



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Test of the mechanical compatibility

Digital Optical Hybrid

Interconnect Board

Analogue Optical Hybrid

Frontend Hybrid

R#1

R#3

R#5

R#7

R#2

R#4

R#6


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First optical readout of TEC Module: Lyon


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Signal Integrity

Reset Pulse Differential Bunch Clock Pulse


Over-voltage measurements

Behaviour of full loaded system due to sudden variation in current

consumption (switching off the frontend hybrids)

over-voltage swing due to inductance of the long cables

over-voltage gradient due to slow reaction time of the PSU


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Setup for the Measurements of the Over-voltage



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I250 = 1.2 AI125 = 0.52A

Over-voltage swing due to cable inductance

o Commercial power supplies o Sense wires not connected o Cable Length = 100mo Different dumping capacitances

I250 = 2.75 AI125 = 0.84 A

I250 = 1.0 AI125 = 0.52 A

Overvoltage measurementsC250 = 60 µF, C125 = 40 µF

C250 = 330 µF, C125 = 330 µF C250 = 740 µF, C125 = 740 µF

V2.50

V1.25

V2.50

V1.25

V2.50

V1.25


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Over voltage is a potential problem.

o Overvoltage gradient requires : special power supply design or radhard voltage limiter located close to detector could be reduced by proper system architecture

o Overvoltage swing could be fixed by: reasonable damping capacitance on the interconnect boards

Over-voltage measurements

Overvoltage gradientdue to slow regulation time of PSU

o senses wires connectedo commercial power supplyo dumping capacitance 700µFo cable 100m, U = 0.8Vo 4 frontend hybrids toggled; I = 2A

Overvoltage .4 V above the limit


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Conclusions and Remarks

o System test is underway for TIB/TOB/TEC

o The goal is to test an overall performance of a complete subsystem:

Si-Modules + FE-electronics / analogue optical links / digital control links /long cables / power supplies /monitoring

o It´s intended to be a step by step process All sub-components will be integrated as soon as they are made available

o First TOB Rod is integrated, ready to start quantitative measurements

o Final results for all detectors are expected by the beginning of 2003

cms tracker system test

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